Apple has released the iMac Graphic FW Update 2.0 via their Software Update utility and website for direct download. According to the release notes, this firmware update fixes an issue that in rare cases may cause an iMac to hang during startup or waking from sleep. The company also notes that users should not shut off the power on their iMac during this update. Loss of power could result in your iMac failing to start up. The iMac Graphic FW Update 2.0 weighs in at 699KB and requires Mac OS X 10.6.7.